Abstract: A method of producing high purity polyol esters comprises reacting a polyol with an excess amount of a linear or branched aliphatic monocarboxylic C3-20 acid to esterify less than the total amount of the polyol present to form an intermediate reaction composition having a hydroxyl value of from 7 to about 50 mg KOH/g. An anhydride of the corresponding linear or branched aliphatic monocarboxylic C3-20 acid is added to the intermediate reaction composition in an amount of from 1 to about 2.5 equivalents of available OH in the intermediate composition to form a reaction mixture. The reaction mixture is heated for 5-30 minutes or until all of the corresponding anhydride has reacted to form a reaction product. The reaction product is then de-acidified. No metal or acid catalyst or bleaching agents are present in any of the above reaction steps at a concentration above about 15 ppm.

Abstract: A method of producing high purity polyol esters comprises reacting a polyol with an excess amount of a linear or branched aliphatic monocarboxylic C3-20 acid to esterify less than the total amount of the polyol present to form an intermediate reaction composition having a hydroxyl value of from 7 to about 50 mg KOH/g. An anhydride of the corresponding linear or branched aliphatic monocarboxylic C3-20 acid is added to the intermediate reaction composition in an amount of from 1 to about 2.5 equivalents of available OH in the intermediate composition to form a reaction mixture. The reaction mixture is heated for 5-30 minutes or until all of the corresponding anhydride has reacted to form a reaction product. The reaction product is then de-acidified. No metal or acid catalyst or bleaching agents are present in any of the above reaction steps at a concentration above about 15 ppm.